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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Aplinkosauginių Tūkstantmečio vystymosi tikslų įgyvendinimas Lietuvoje / The environment realisation of Millennium development goals in Lithuania

Sabaliauskaitė, Viktorija 14 June 2010 (has links)
Tūkstantmečio vystymosi tikslai tai viso pasaulio valstybių indėlis, sprendžiant visuotines problemas ir užtikrinant kiekvienos šalies gyventojų gyvenimo sąlygas atsižvelgiant į aplinkos tausojimą bei darnaus vystymosi užtikrinimą. Šio darbo tikslas ir yra išanalizuoti bei įvertinti aplinkosauginių Tūkstantmečio vystymosi tikslų įgyvendinimą Lietuvoje 1990-2008 metų laikotarpius. Siekiant įvertinti gyventojų nuostatas bei požiūrį Tūkstantmečio vystymosi tikslų atžvilgiu, buvo atliekama gyventojų apklausa, sudaryto klausimyno pagalba. Kiekvienos valstybės padėtį, įgyvendinant Tūkstantmečio vystymosi tikslus nusako numatytų rodiklių įgyvendinimo lygis. Lietuvoje, siekiant užtikrinti darnią aplinkos apsaugą yra stebimi šie rodikliai: miškingos ir saugomų teritorijų dalis, biologinės įvairovės ir rūšių, kurioms gresia išnykimas išsaugojimas, anglies dioksido dujų ir ozono pirmtakų emisija bei bendras vandens išteklių suvartojimas šalyje. Atskaitos taškas, nuo kada stebimas rodiklių kitimas yra 1990 metai, o numatyti tikslai turi būti pasiekti, pagal Tūkstantmečio deklaraciją, iki 2015 metų. Vykdant gyventojų apklausą buvo nustatyta, jog didžioji dauguma, 74 % apklaustųjų, nėra girdėję apie Tūkstantmečio vystymosi tikslus. 26 % respondentų, kurie žino, apie šiuos pasaulinius tikslus yra įgiję universitetinį išsilavinimą (67 %). Atliekant rangavimą, gyventojų nuomone svarbiausi Tūkstantmečio vystymosi tikslai yra skurdo ir bado panaikinimas pasaulyje, vaikų mirtingumo mažinimas... [toliau žr. visą tekstą] / Millennium development goals – all world countries input in solving universal problems and assuring living conditions for every country‘s citizens, also considering environment and sustainable development aspects. The aim of this work is to analyse and evaluate the implementation of environmental Millennium development goals in Lithuania during 1990-2008. In order to evaluate people attitudes in regard to Millennium development goals, population survey was conducted, with the help of questionnaire. Implementation level of foreseen indicators indicates every country’s progress in implementing Millennium development goals. In Lithuania, pursuing to assure sustainable environment protection, such indicators are observed: parts of forested and protected territories, protection of biological diversity and species, which are at risk of extinction, emission of carbon dioxide and ozone prosecutors and general water consumption in the country. Year 1990 is a starting point. According to Millennium declaration, the intended aims must be reached up to 2015. Survey reveals that the majority – 74 % of respondents have not heard about Millennium development goals. 26 % of respondents, who are aware of those global aims, hold a university degree (67 %). In citizens’ opinion, most important Millennium development goals are elimination of poverty and hunger in the world, reducing of children’s death-rate and assurance of friendly environment. These aims were named as very important by... [to full text]
212

The sustainability of donor funded projects in the health sector / T. Mitchell

Mitchell, Therese January 2013 (has links)
The need for donor funding has increased significantly over the last decade. Without donor funding millions of people wouldn’t be alive today. Thanks either to research finding a cure, successful treatment, funds donated for food, aid toward building infrastructure, or giving people the opportunity to further their education. Donor funding thus facilitates a better future. A literature review was conducted to give background on the health sector and how these funds were distributed, ethical clearance, different types of reporting, the role project managers pays in a project and the sustainability of projects. Expenses in different countries were evaluated by gathering data from the internet, while two international funded projects are also used to state how funders divide their line items into different categories. The empirical study used a qualitative research approach by collecting and analysing data obtained from the MDG 2010 report and other freely available data on the web. The main findings from this thesis are: *The Millennium Development Goals (MDG’s) influence donor funding as it gives donors a guide towards funding needs. Donors are also influenced by their own preferences or what poses a burden to them individually. *The different types of reporting required for funding received, delay a project and the bureaucratic structures thereof are a hindrance. *Ethical clearance plays a fundamental role in the outcome of a project, as without ethical clearance a project cannot commence. *The objectives of a project play a critical role when applying for funding. This can change the focus of a project. *Expenses differ from country to country and funders need to take this into account when giving funding to recipient countries. *Project Managers and community involvement plays a critical role in ensuring sustainability of projects. THE SUSTAINABILITY OF DONOR FUNDED PROJECTS IN THE HEALTH SECTOR *The MDG’s are not on track and aid are focus on singular goals instead of multiple goals, to ensure an overall improved result. There is a major gap between needed funds and given funds. A single injection of funds will not be the solution to our health problem; different sectors need to collaborate together as we are facing a multi-dimensional problem. Trade and reform must also form part of this aid, ensuring a sustainable progression in the life’s of people. Donor funded projects may have a sustainable future, when taking in account the abovementioned findings. With the world trend in reporting changing rapidly, cost and management accountants as well as financial accountants and project managers have to equip them to adhere to the new way of reporting, namely integrated and sustainability reporting. South Africa is way behind and needs to catch up fast if they want to stay competitive in the “global donor funding market”. The limitations in this study were that not all expenses were evaluated and only 15 countries were looked at. An indebt look was taken into Africa with the empirical review, while Asia is also combating poor health issues. Some African countries like Sierra Leone and Zimbabwe did not have sufficient data to compare with other countries. From the research conducted, the following topics were identified that require further research: *Why are most projects in Third World countries not sustainable? *What plans are put into action to ensure that the MDG goals are reached? *Investigate what works for First World countries health systems and consider how that can be applied to Third World countries to ensure that they also get the best health care available. *Do donors take into account the different costs of countries when allocating funding to that specific country? *Establishing models to evaluate the sustainability of pilot projects and normal projects. *Establishing a model on how to distribute donor funds across different needs and not only one specific need. / MCom (Management Accountancy), North-West University, Vaal Triangle Campus, 2013
213

Perceptions of rural water service delivery : the case of Ugu District Municipality / Timothy Bheka Cele

Cele, Timothy Bheka January 2012 (has links)
The start of the 21th century is notable for the apparent lack of safe drinking water and sanitation. Over one billion people in all parts of the world lack access to clean water. Most live in developing countries, such as Africa. Unsafe water and poor sanitation have been primary causal factors in the vast majority of water-borne diseases, especially diarrheal ones. The South African Constitution (Act 108 of 1996, Chapter 2, Section 24) states: “Everyone has the right: (a) To an environment that is not harmful to their health and their wellbeing; and (b) To have the environment protected, for the benefit of present and future generations, through reasonable legislative and other measures that prevent pollution and ecological degradation; promote conservation; ecologically sustainable development, and the use of natural resources, while promoting justifiable economic and social development.” Secondly, section 27 states that: “Everyone has the right to have access to: (a) Health-care services, including reproductive health care; (b) Sufficient food and water; and (c) Social security, including, if they are unable to support themselves and their dependants, appropriate social assistance.” These factors have prompted this research within the Ugu District Municipality on the perceptions of inadequate rural water service delivery. This study reveals information on those areas in the Ugu District Municipality, which do not have access to clean water, and on the health hazards that might lead to death if residents’ lack of access to clean water persists. The Ugu District Municipality, is situated in KwaZulu-Natal Province, and covers a surface area of 5866 km2. There are six local municipalities in this district. These are: Ezinqoleni, Umzumbe, Umziwabantu, Hibiscus Coast, Umdoni and Vulamehlo. The node is 77% rural and 23% urban, and the total population for this area is 704027 (Ugu District Municipality IDP 2nd 2011/2012:19). / M. Development and Management (Water Studies), North-West University, Potchefstroom Campus, 2012
214

Perceptions of rural water service delivery : the case of Ugu District Municipality / Timothy Bheka Cele

Cele, Timothy Bheka January 2012 (has links)
The start of the 21th century is notable for the apparent lack of safe drinking water and sanitation. Over one billion people in all parts of the world lack access to clean water. Most live in developing countries, such as Africa. Unsafe water and poor sanitation have been primary causal factors in the vast majority of water-borne diseases, especially diarrheal ones. The South African Constitution (Act 108 of 1996, Chapter 2, Section 24) states: “Everyone has the right: (a) To an environment that is not harmful to their health and their wellbeing; and (b) To have the environment protected, for the benefit of present and future generations, through reasonable legislative and other measures that prevent pollution and ecological degradation; promote conservation; ecologically sustainable development, and the use of natural resources, while promoting justifiable economic and social development.” Secondly, section 27 states that: “Everyone has the right to have access to: (a) Health-care services, including reproductive health care; (b) Sufficient food and water; and (c) Social security, including, if they are unable to support themselves and their dependants, appropriate social assistance.” These factors have prompted this research within the Ugu District Municipality on the perceptions of inadequate rural water service delivery. This study reveals information on those areas in the Ugu District Municipality, which do not have access to clean water, and on the health hazards that might lead to death if residents’ lack of access to clean water persists. The Ugu District Municipality, is situated in KwaZulu-Natal Province, and covers a surface area of 5866 km2. There are six local municipalities in this district. These are: Ezinqoleni, Umzumbe, Umziwabantu, Hibiscus Coast, Umdoni and Vulamehlo. The node is 77% rural and 23% urban, and the total population for this area is 704027 (Ugu District Municipality IDP 2nd 2011/2012:19). / M. Development and Management (Water Studies), North-West University, Potchefstroom Campus, 2012
215

The complementarities of child health achievements in developing countries

Lo Bue, Maria Carmela 06 February 2015 (has links)
Diese Dissertation basiert auf einer auf den Menschen bezogenen, multidimensionalen Betrachtung von Entwicklung. Sie soll empirisch Übereinstimmungen und Determinanten der Gesundheit von Kindern in Ländern mit niedrigem und mittlerem Einkommen analysieren. Der erste Essay – mit verfasst von Stephan Klasen - wendet bivariate Cluster Analyse an, um die Beziehung der Verbesserungen verschiedener Gesundheits- und Bildungsindikatoren der Millennium Development Goals (MDG) zu untersuchen. Die MDGs beinhalten Schlüsselaspekte des menschlichen Wohlbefindens und sollten daher eng miteinander verkoppelt sein. Trotz der substantiellen theoretischen Grundlage für enorme Synergien zwischen MDG Zielen, ist die empirische Heterogenität der Kopplung der Prozesse zwischen verschiedenen MDGs erheblich groß.  Die zentrale Fragestellung des ersten Essays dieser Dissertation ist daher, ob klare Gruppen eben jener Länder ausgemacht werden können, in denen derartige Synergien existieren (und in denen diese nicht existieren), und was die Zugehörigkeit in derartigen Gruppen treibt.   Unser Beitrag ist, den MDG Fortschritt durch Indikatoren relativer Leistung zu definieren. Diese bezeichnen die Änderungsrate, die die empirisch "erwartete" Änderungsrate bei gegebenen ursprünglichen Bedingungen übersteigt. Diese Maßnahme erlaubt es uns für den unterschiedlichen Grad an Ambition impliziert durch die MDGs bei Ländern mit unterschiedlichen Ausgangslagen zu kontrollieren und lässt uns im Grunde fragen ob Länder, die außerordentlichen Fortschritt bei der Erreichung von MDGs gemacht haben, von Synergien profitiert haben. Indem wir die Cluster Analyse auf diese Indikatoren der relativen Leistung in Bezug auf verschiedene MDG Indikatoren für Gesundheit und Bildung anwenden konnten wir jene Länder, in denen sich Indikatoren in die selbe Richtung ("gute" oder "schlechte" Performer) bewegten, von solchen Ländern unterscheiden, bei denen sich Indikatoren in unterschiedliche Richtungen ("partielle" Performer) bewegten. Unsere Ergebnisse legen nahe, dass Synergien existieren, diese jedoch nur bei einer eingeschränkten Gruppe von Ländern auftreten (die "guten" Performer, die mit Fortschritt einhergehen und die "schlechten" Performer, die mit Rückschritt einhergehen). Andererseits können wir zeigen, dass bei einer beträchtlichen Anzahl an Ländern Synergien schwach oder abwesend sind, was zu umgekehrten Bewegungen  im MDG Fortschritt bei mindestens einem oder zwei Paaren von nicht einkommensbezogenen MDG Indikatoren führt. Unsere Regressionsergebnisse zeigen, dass diese partielle Performance gut durch steigende Ungleichheit und niedrige institutionelle Qualität erklärt wird. Andererseits kann Wirtschaftswachstum, welches als die robusteste Determinante der Cluster-Zugehörigkeit erscheint, insbesondere gute von schlechten Performern unterscheiden. Der zweite Essay - in alleiniger Urheberschaft - analysiert die kurz- und langfristigen Determinanten von Errungenschaften bei der Gesundheit von Kindern unter Verwendung von Längsschnittsdaten aus Indonesien. Basierend auf dem analytischen Ansatz von Mosley und Chen (1984), werden insbesondere die Effekte einer Reihe von kindspezifischer, Haushalts- und Gemeindecharakteristika auf den Ernährungszustand von Kindern, gemessen in height-for age z-scores, betrachtet. Der besondere Beitrag dieser Studie ist die Verwendung von Paneldaten auf der Mikro-Ebene und einer Methodologie (dem Mundlak-Ansatz für fixe  Haushalteffekte), die  robuste und unverzerrte Schätzungen liefert. Desweiteren ermöglicht sie die Identificationkurz- und langfristiger Effekte unmittelbarer und sozioökonomischer Determinanten der Gesundheit von und trägt so zur bestehenden Literatur bei. Die Ergebnisse legen nahe, dass mütterliche Bildung einen positiven und langfristigen Einfluss auf die Gesundheit von Kindern hat. Dies zeigt sich teilweise in reproduktivem Verhalten und wird teilweise durch Praktiken im Umgang mit Kindern (d.h. Stillen) vermittelt. Andererseits zeigt sich kein langfristiger Effekt von Einkommen, obgleich temporäre Einkommenssteigerungen zu höheren Ausgaben und somit zu einer Verbessereung des Eernährungsstatus führen., Hierbei zeigt nur der Erwerb und die Verwendung von Vorleistungsgütern der Gesundheitsproduktion wie einer verbesserten Hygieneinfrastruktur einen ausgeprägten und signifikanten Einfluss auf die Gesundheit von Kindern. Insgesamt implizieren die Ergebnisse, dass eine Politik der Linderung von Einkommensarmut ergänzt durch Investitionen in grundlegende Gesundheitsinfrastruktur erheblich dazu beitragen, die Gesundheit von Kindern zu verbessern. Da der Zusammenhangzwischen der Bildung von Müttern, Praktiken der Kindesernährung und der Gesundheit von Kindern stark ausgeprägt ist, könnten auch Strategien, die die Qualität von Bildung erhöhen,  den Ernährungszustand von Kindern verbessern. Der dritte Essay - in alleiniger Urheberschaft - untersucht die Auswirkungen des Ernährungszustandes auf den Bildungserfolg. Dabei werden Paneldaten auf der Miko-Ebene aus Indonesien verwendet. Außerdem wird eine Spezifikation mit Mutter-Fixed Effects, die durch einen Instrumentalvariablen-Ansatz erweitert wird, verwendet um für mögliche Korrelationen zwischen verschiedenen Komponenten des Fehlerterms und der unabhängigen Variable zu kontrollieren. Wir nutzen Flächenbrände, die im Jahr 1997 in Inodensien zu einer Dürre führten, und Variation zwischen Geschwistern und identifizieren so den Effekt des Ernährungszustands in den frühen Lebensmonaten auf den späteren Bildungserfolg. Schätzungen zeigen, dass Gesundheitskapital (gemessen in height-for-age z-scores in der Kindheit) die Anzahl an abgeschlossenen Schuljahren und das Ergebnis bei kognitiven Testes signifikant positiv beeinflusst.  Dies impliziert, dass von einer politischen Perspektive aus Zielsetzungen im Bereich Schule und Ernährung nicht als rivalisierend betrachtet werden sollten, sondern eng miteinander verzahnt sind. Daher konkurrieren finanzielle Ressourcen, die der Kindesernährung gewidmet sind, nicht unbedingt mit solchen für Bildungszwecke. Im Gegensatz könnten sie - wie in diesem Essay beschrieben - als eine kosteneffizientere Art betrachtet werden, gegenwärtige und zukünftige sozio-ökonomische Entwicklung anzuheben.
216

A multilevel analysis of learner and school contextual factors associated with educational quality

Winnaar, Lolita January 2013 (has links)
Magister Philosophiae - MPhil / The South African schools act, (number 5, 1996), asserts that all learners have a right to access both basic and quality education without discrimination of any sort. Since the implementation of the Millennium Development Goals there has been a drive by the Department of Education to ensure that all learners have access to basic education by 2015. However what remains a challenge after almost 20 years of democracy is the poor quality of education and this is clear from the results of international assessment studies. Results from studies like the Trends in International Mathematics and Science Study and Southern and East Africa Consortium for Monitoring Educational Quality, show that South African children perform well below international averages. In this study learner Mathematics achievement scores taken from the Trends in International Mathematics and Science Study 2011 cycle will serve as a proxy for educational quality. Using multilevel analysis the current study aims to use a 2-level Hierarchical Linear Model to firstly; determine the learner and family background factors associated with education quality. Secondly; factors at the school level will be identified and proven to be associated with education quality. Variables selected for the study was based on Creamer’s theory of school effectiveness which looked at school, classroom level inputs as well as learner background variables to explain student level achievement. The results show that at the learner’s level the most significant factors were the age of the leaner, in the sense that grade age appropriate learners obtained higher scores than overage learners. Learner’s perception of mathematics is extremely important and has a positive effect on mathematics performance. In the current study mathematics perception refers to learners valuing and liking mathematics as well learner confidence in learning mathematics. Learners who said they were bullied as school generally scored lower than learners who were not bullied. At the school level the most significant factors were teacher working conditions, teachers’ specialisation in mathematics, school socio-economic status, and general infrastructure. Interesting to note at the school level is when socioeconomic status was included in the model as a single variable the score difference between low socio-economic status and high socio-economic status schools was almost 46 points. However when the factors mentioned above were added to the model the difference in scores dropped by almost half.
217

Assessment of Drinking Water Quality Management and a Treatment Feasibility Study for Brick by Brick Water Storage Tanks in Rakai Uganda

Murduca, James V. 23 March 2018 (has links)
Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice survey and a sanitary inspection; tested the water quality of the Brick by Brick rainwater harvesting tanks (N = 33) in the Rakai District for physical, chemical, and microbial parameters; and piloted a sustainable treatment technology called the chulli system that uses excess heat from a cookstove to treat water. Twenty of the participants identified contaminated water as a cause of diarrheal disease (N = 28). Participants perceived boiling (1), chlorine (2), and filtering (3) as the best three methods of treating water. The average score for the sanitary inspection was 2.27±2.31, which falls between the low and medium expected risk score categories. Fourteen of the thirty-three samples showed detectable levels of colony forming units for coliforms, and two of the thirty-three samples showed detectable levels of colony forming units for E. coli. A demonstration chulli system was constructed for St. Andrew’s Primary School in Rakai District and operated successfully. The research supports that the chulli system along with proper sanitation measures identified in the sanitary inspections can be a sustainable option for users of Brick by Brick rainwater harvesting tanks in the Rakai District.
218

Global Partnerships for Sustainable Development - a case study of the Global Deal for Decent Work and Inclusive Growth

Palling Huusko, Susanna January 2018 (has links)
This thesis discusses global partnerships for sustainable development. Global partnerships have come to be considered as key tools for the implementation of certain international sustainable development goals and there is a growing literature on the subject. Nevertheless, no study has yet been done of the Global Deal Partnership for Decent Work and Inclusive Growth, initiated by the Government of Sweden in 2016. The partnership is presented as a concrete input to several of the Sustainable Development Goals, especially numbers 8, 10, and 17. This provides an important opportunity to make sense of the Global Deal partnership, in particular since it is the first attempt of its kind to unite all stakeholders on the global labour market to work together to provide decent work and inclusive growth for all. What are the goals of the Global Deal, how was it formed, and how is it being implemented? The analysis presented in this thesis is based on a literature survey, documentary analysis, and interviews with the Global Deal Partnership’s support unit at the Swedish Ministry for Foreign Affairs. This thesis argues that the Global Deal partnership is a textbook example of a global multi-stakeholder partnership, developed through an inclusive goal-setting process, and implemented with monitoring and reporting functions.
219

PSF e ODM: a influência do Programa Saúde da Família para os estados brasileiros atingirem a meta de mortalidade na infância dos objetivos de desenvolvimento do milênio

Pedro, Márcio Vinícius 24 September 2014 (has links)
Made available in DSpace on 2016-06-02T19:15:03Z (GMT). No. of bitstreams: 1 6431.pdf: 1795909 bytes, checksum: f53b24dcea4cd392276f6f4fba9db718 (MD5) Previous issue date: 2014-09-24 / Financiadora de Estudos e Projetos / What influence Family Health Program‟ (in portuguese, Programa Saúde da Família, or PSF) had on Brazilian states in their attempt to achieve the Millennium Development Goals - especially on reducing infant mortality until 2015? In 2000, the United Nations along with global leaders established an international research agenda with eight Millennium Development Goals, intending to promote human dignity. The purpose of the present thesis is to evaluate the influence of the Family Health Program - the main strategy to reformulate the basic care - in reducing child mortality within Brazilian states. For this matter, I analyze descriptive and inferential statistics, with bi and multivariate techniques, and data from DATASUS, IBGE and SIGO databases. The present thesis covers the period from 2000 to 2011, when Brazil reached the goal. Throughout this time ten states went above the goal specified by ODM (1,79): in all of them the Program had low range. However, the states with higher PSF range presented higher average rates of reduction of infant mortality. Overall, the hypothesis that PSF has a positive influence on reducing infant mortality rate can be confirmed, considering that the states with higher reduction of the rate had a higher proportion of population benefiting from the PSF. / Qual a influência do Programa Saúde da Família para os estados brasileiros atingirem a meta do Objetivo de Desenvolvimento do Milênio redução da mortalidade na infância, até 2015? No ano 2000 a Organização das Nações Unidas em conjunto com líderes mundiais estabeleceu uma agenda global com oito Objetivos de Desenvolvimento do Milênio que visavam a promoção da dignidade humana. O objetivo deste trabalho é analisar a influência do Programa Saúde da Família, principal estratégia de reformulação da atenção básica, na redução da mortalidade na infância nos estados brasileiros. Para tanto, fazemos uso de estatística descritiva e inferencial, com técnicas de análise bi e multivariada, analisando dados oriundos do DATASUS, IBGE e SIGO. O recorte temporal foi de 2000 a 2011, ano que o Brasil atingiu a meta. Nesse período dez estados bateram a meta de 17,9 de mortalidade na infância estipulada pela ODM, todos com baixa cobertura do PSF. Contudo, os estados com maior cobertura apresentaram maior média de redução da taxa de mortalidade na infância. De modo geral foi possível afirmar que hipótese se confirma, isto é, existe uma influência positiva do PSF na diminuição da mortalidade infantil havendo uma maior redução da taxa nos estados com maior proporção populacional coberta.
220

Pathogen Removal in Natural Wastewater Treatment and Resource Recovery Systems: Solutions for Small Cities in an Urbanizing World

Verbyla, Matthew Eric 17 November 2015 (has links)
Sanitation, renewable energy, and food security are among the most pressing global development needs of the century, especially for small cities with rapid population growth. Currently, 53% of the world’s population either lacks access to improved sanitation or discharges fecal waste to the environment without treatment. Furthermore, 80% of food consumed in developing regions is produced by 500 million small farms, and while many of them are still rain-fed, irrigated agriculture is increasing. The post-2015 Sustainable Development Goals, recently adopted by the United Nations, include targets to address the water-energy-food nexus. Wastewater reuse in agriculture can be an important solution for these goals, if it is done safely. Globally, 18 – 20 million hectares of agricultural land are irrigated with wastewater, but much is untreated, unregulated, or unsanctioned, causing concerns and uncertainty about health risks. There is a need to better understand pathogen removal in natural and non-mechanized wastewater treatment systems, such as waste stabilization ponds (WSPs) and upflow anaerobic sludge blanket (UASB) reactors, which are commonly used in small cities and towns. Riverbank filtration (RBF) is also a natural technique used by farmers in developing countries to treat surface water polluted with untreated sewage, but pathogen removal in these systems has seldom been assessed in developing countries. The focus of this dissertation is on pathogen removal in natural and non-mechanized wastewater treatment and reuse systems, to evaluate the health implications of water reuse for irrigation, with the following three objectives: 1) assess the current understanding of virus removal in WSP systems through a systematic review of the literature; 2) measure the removal of viruses and their association with particles in systems with WSPs, UASB reactors, or both; and 3) assess the fate and transport of pathogens and fecal indicators in wastewater treatment systems with direct and indirect reuse for irrigation to estimate microbial risks. To advance the understanding of virus removal in WSP systems, a comprehensive analysis of virus removal reported in the literature from 71 different WSP systems revealed only a weak to moderate correlation of virus removal with theoretical hydraulic retention time (HRT). For each log10 reduction of viruses a geometric mean of 14.5 days of retention was required, but the 95th percentile of the data analyzed was 54 days. Also, whereas virus-particle association and subsequent sedimentation has been assumed to be an important removal mechanism for viruses in WSPs, the literature review revealed a lack of evidence to confirm the validity of this assumption. The association of human adenovirus (AdV) with wastewater particles was assessed in five full-scale wastewater treatment systems in Bolivia, Brazil, and the United States (two with only WSPs, two with a UASB reactor and WSPs, and one with only UASB reactors). A mesocosm study was also conducted with WSP water from one of the full-scale systems, and some samples were also analyzed for pepper mild mottle virus (PMMoV), F+ coliphage, culturable enterovirus (EV), norovirus (NoV), and rotavirus (RV). Results indicate that WSPs and UASB reactors affect virus-particle associations in different ways, which may differ for different viruses. In UASB reactor effluent, PMMoV was more associated with particles <180 >µm, showed no indication of settling in subsequent ponds, and appeared to degrade in pond sediments after 5 days. In contrast, AdV in UASB reactor effluent was associated with small and large particles, and in subsequent ponds, particle-associated AdV showed evidence of possible settling or more rapid decay at the water surface. AdV and culturable EV were also more volumetrically-concentrated in UASB reactor sludge than they were in untreated sewage, WSP water, UASB effluent, and WSP sediments, indicating that the reactors may cause these viruses to become entrapped and concentrated in granular sludge. Some viruses may be removed in the sludge, but others exit the reactors in solution and attached to particles. The resuspension of pellets from centrifuged UASB reactor sludge samples in an eluant buffer indicated reversible AdV association with granular sludge, but some associations with particles in solution may not be reversible. The fate and transport of pathogens and fecal indicators was assessed in Bolivia for two WSP systems with direct reuse for irrigation, and one on-farm RBF system used to treat surface water polluted by untreated sewage. In the WSP systems, despite HRTs of 10 days, pathogen and fecal indicator removal was generally ≤1-log10, possibly due to overloading and short-circuiting from sludge accumulation. The RBF system provided removals on the order of 2-log10 for protozoan parasites, 3-log10 or more for viruses, and 4-log10 or more for bacteria. The use of RBF also reduced cumulative estimated health burdens associated with irrigated lettuce. Irrigation of lettuce with untreated river water caused an estimated disease burden that represents 37% of the existing burden from acute diarrhea in Bolivia; when RBF was used, this decreased to only 1.1%, which is not epidemiologically-significant, and complies with the World Health Organization guidelines. Ratios of concentrations of microorganisms in irrigation water to their respective concentrations in soil or crops were calculated, to assess transfer from irrigation water to soil or crops. These ratios (with units mL g-1) were generally < 0.1 mL g-1 for coliphage, between 1 and 100 mL g-1 for Giardia and Cryptosporidium, and generally between 100 and 1,000 mL g-1 for helminth eggs. Higher ratios could indicate more efficient transfer from water to soil or crops, longer persistence in soil or on crops, or slower leaching away from soil or crops. The results from this research demonstrate that pathogen removal in full-scale natural wastewater treatment systems happens via complex mechanisms that vary with respect to pathogen type, treatment systems configuration, and other environmental and operational parameters. Future research and innovation efforts should focus on the use of a combination of natural and non-mechanized technologies, surface-flow systems (e.g., WSPs) and subsurface systems (e.g., RBF), applied at both semi-centralized (e.g., wastewater treatment plant) and decentralized levels (e.g., on farms), to evaluate how this affects the efficiency and resiliency of pathogen removal. Also, future research is needed to further elucidate reasons for the observed differences in virus-particle associations in natural wastewater treatment systems.

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